Current and future generations of composite airplanes may extensively use fiber optic cables for size, weight, cost and EMI reduction. The number of fiber optic cables in a composite airplane may be many times that which is used in a conventional metal frame airplane. As the number of fiber optic cables increases, the potential for distortions which may arise in the optical fiber cable during installation may need to be addressed. Distortions in the fiber optic cables are rare and in some applications it may be desirable to verify their absence from the cables.
Due to the high density of fiber optic cable in the cable bundle, optical fibers may be bundled in tight spaces near the connector panel. Most distortions in the cable may occur at locations near the cable's end face which is coupled to the LRU (line replaceable unit) connectors' termini or inside its own termini. Conventional equipment (such as photon-counting, Michelson Interferometer, Optical Backscatter Reflectometer) for cable distortion detection may detect distortions in fiber optic cable with highest resolution of 5 cm. But these cable distortion detecting equipments that can detect cable distortions at a distance of less than 5 cm from the end face of the cable may be expensive, bulky, heavy and have limitations for testing multi-mode (MM) glass fiber and large core plastic optical fiber (POF). They are not suitable for field use onboard airplanes during the cable installation process.
Therefore, a low-cost, compact and easy-to-use fiber optic cable distortion detection system is needed for fiber optic cable installation.